Introduction to AutoCAD 2008 2D and 3D Design phần 4 pdf

The command line shows: Command: _dimlinear Specify first extension line origin or select object: pick Specify second extension line origin: pick Non-associative dimension created.. The

3 Using the tools Polyline, Circle, Trim, Polyline Edit, Mirror and Fillet construct the drawing in Fig 5.48.

4 Construct the circles and lines (Fig 5.49) Using Offset and the Ttr prompt of the Circle tool followed by Trim, construct one of the outlines arrayed within the outer circle Then, with Polyline Edit, change the lines and arcs into a pline of width  0.3 Finally

array the outline twelve times around the centre of the circles(Fig 5.50)

Fig 5.49 Exercise 4 – circles and

lines on which the exercise is based

5 Construct the arrow (Fig 5.51) Array the arrow around the centre of

its circle eight times to produce the right-hand drawing of Fig 5.51

6 Construct the left-hand drawing of Fig 5.52 Then with Move, move

the central outline to the top left-hand corner of the outer outline Then

with Copy make copies to the other corners.

∅20 R15

9 Construct the left-hand drawing of Fig 5.55 Include the dimensions in your drawing Then, using the Stretch tool, stretch the drawing,

including its dimensions to the sizes as shown in the right-hand

draw-ing The dimensions are said to be associative (see Chapter 6).

10

R90 Polar Array

16 times in angle 180 ° Fig 5.56 Exercise 10

10 Construct the drawing in Fig 5.56 All parts of the drawing are plines

of width 0.7 The setting in the Array dialog is to be 180 in the

Angle of array field.

CHAPTER 6

Dimensions and Text

Aims of this chapter

1 To describe the variety of methods of dimensioning drawings.

2 To describe methods of adding text to drawings.

Introduction

We have already set a dimension style (My_Style) in the acadiso.dwt

template, so we can now commence adding dimensions to drawings usingthis dimension style

The Dimension tools

There are several ways in which the dimensions tools can be called

1 From the Dimensions control panel in the DASHBOARD (Fig 6.1).

2 Click Dimension in the menu bar Tools can be selected from the

drop-down menu which appears

Fig 6.1 Dimension tools in the

Dimensions control panel

Fig 6.2 The Linear tool icon in

the Dimensions control panel

3 From the Dimension toolbar The toolbar can be called to screen with

a right-click in any toolbar on screen followed by a click on

Dimen-sion in the popup menu which appears.

4 By entering an abbreviation for a dimension tool at the command

line

Any one of these methods can be used when dimensioning a drawing,but some operators may well decide to use a combination of the fourmethods

Adding dimensions using the tools

First example – Linear dimension (Fig 6.3)

1 Construct a rectangle 180  110 using the Polyline tool.

2 Left-click the Linear tool icon in the Dimensions control panel

(Fig 6.2) or on Linear in the Dimension toolbar The command

line shows:

Command: _dimlinear Specify first extension line origin or select object: pick

Specify second extension line origin: pick

Non-associative dimension created.

Specify dimension line location or [Mtext/Text/Angle/Horizontal/

1 If necessary use Osnaps to locate the extension line locations.

2 The prompt Specify first extension line origin or [select object]: also

allows the line being dimensioned to be picked.

first extension line

second extension line

dimension line location

180

Fig 6.3 First example – Linear

dimension

Fig 6.4 The Aligned tool icon in

the Dimensions control panel

Fig 6.6 The Radius tool icon in

the Dimensions control panel

Second example – Aligned dimension (Fig 6.5)

1 Construct the outline in Fig 6.5 using the Line tool.

2 Left-click the Aligned tool icon (Fig 6.4) and dimension the outline.

The prompts and replies are similar to the first example

Third example – Radius dimension (Fig 6.7)

1 Construct the outline in Fig 6.7 using the Line and Fillet tools.

2 Left-click the Radius tool icon (Fig 6.6) The command line shows:

Fig 6.8 A radius dimension at an

angle of 45 

2 If the response is a (Angle), and an angle number is entered the text

for the dimension will appear at an angle Fig 6.8 show a radius

dimension entered at an angle of 45

3 If the response is m (Mtext), the Text Formatting dialog appears

together with a box in which new text can be entered See page 120.

4 Dimensions added to a drawing using other tools from the Dimensions control panel or from the Dimension toolbar should be practised.

Adding dimensions from the command line

From Fig 6.1 it will be seen that there are some dimension tools which

have not been described in examples Some operators may prefer entering

dimensions from the command line This involves abbreviations for therequired dimension such as:

For Linear dimension – hor (horizontal) or ve (vertical) For Aligned dimension – al

For Radius dimension – ra For Diameter dimension – d For Angular dimension – an For Dimension Text Edit – te For Quick Leader – l

And to exit from the dimension commands – e (Exit).

First example – hor and ve (Horizontal and vertical) – Fig 6.10

1 Construct the outline in Fig 6.9 using the Line tool Its dimensions are

shown in Fig 6.10

2 At the command line enter dim The command line will show:

Command: enter dim right-click Dim: enter hor (horizontal) right-click

Specify first extension line origin or select object: pick

Specify second extension line origin: pick

Non-associative dimension created.

Specify dimension line location or [Mtext/Text/Angle]: pick

Enter dimension text 50: right-click

Dim: right-click

Fig 6.9 First example – outline to

dimension

50 140 50

Fig 6.10 First example – horizontal

and vertical dimensions

HORIZONTAL Specify first extension line origin or select object: pick

Specify second extension line origin: pick

Non-associative dimension created.

Specify dimension line location or [Mtext/Text/Angle/Horizontal/

Vertical/Rotated]: pick

Enter dimension text 140: right-click

Dim: right-click

And the 50 and 140 horizontal dimensions are added to the outline

3 Continue to add the right-hand 50 dimension Then when the

com-mand line shows:

Dim: enter ve (vertical) right-click

Specify first extension line origin or select object: pick

Specify second extension line origin: pick

Specify dimension line location or [Mtext/Text/Angle/Horizontal/

Vertical/Rotated]: pick

Dimension text 20: right-click

Dim: right-click

VERTICAL Specify first extension line origin or select object: pick

Specify second extension line origin: pick

Specify dimension line location or [Mtext/Text/Angle/Horizontal/

Vertical/Rotated]: pick

Dimension text 100: right-click

Dim: enter e (Exit) right-click

Command:

The result is shown in Fig 6.10

Second example – an (Angular) – Fig 6.12

1 Construct the outline in Fig 6.11 – a pline of width  1.

2 At the command line:

Command: enter dim right-click Dim: enter an right-click

Third example – l (Leader) – (Fig 6.14)

1 Construct the outline in Fig 6.13.

2 At the command line:

Command: enter dim right-click Dim: enter l (Leader) right-click Leader start: enter nea (osnap nearest) right-click to pick one of the

Select arc, circle, line or specify vertex: pick

Select second line: pick

Specify dimension arc line location or

[Mtext/Text/Angle/Quad-rant]: pick

Enter dimension 90: right-click

Enter text location (or press ENTER): pick

Dim:

And so on to add the other angular dimensions

The result is given in Fig 6.12

Continue to add the other leader dimensions – Fig 6.14.

Fourth example – te (Dimension Text Edit) – (Fig 6.16)

1 Construct the dimensioned drawing in Fig 6.15.

2 At the command line:

Command: enter dim right-click Dim: enter te (tedit) right-click Select dimension: pick the dimension to be changed

Specify new location for text or [Left/Right/Center/Home/Angle]:

either pick or enter a prompt’s capital letter

Dim:

The results as given in Fig 6.16 show dimensions which have been

moved: the 210 dimension changed to the left-hand end of the dimension line, the 130 dimension changed to the left-hand end of the dimension line and the 30 dimension position changed.

The Arc Length tool (Fig 6.18)

1 Construct two arcs of different sizes as in Fig 6.18.

2 Call the Arc Length tool with a click on its tool icon in the sions control panel (Fig 6.17), or with a click on Arc Length in the Dimension toolbar, or by entering dimarc at the command line The

Dimen-command line shows:

Command: _dimarc

Select arc or polyline arc segment: pick an arc

Specify arc length dimension location, or [Mtext/Text/Angle/

Partial/Leader]: pick a suitable position

Fig 6.16 Fourth example –

dimensions amended with tedit

Fig 6.17 The Arc Length tool in

the Dimensions control pane

Fig 6.19 The Jogged tool icon in

the Dimensions control panel

The Jogged tool (Fig 6.20)

1 Draw a circle and an arc as indicated in Fig 6.20.

2 Call the Jogged tool, either with a left-click on its tool icon in the Dimensions control panel (Fig 6.19), or with a click on Jogged in the Dimension toolbar, or by entering jog at the command line The com-

mand line shows:

Before simple tolerances can be included with dimensions, new settings

will need to be made in the Dimension Style Manager dialog as follows:

1 Open the dialog The quickest way of doing this is to enter d at the

command line followed by a right-click This opens up the dialog.

2 Clickthe Modify button of the dialog, followed by a left-click on the

Primary Units tab and in the resulting sub-dialog make settings as

shown in Fig 6.21 Note the changes in the preview box of the dialog

3 Click the Tolerances tab and in the resulting sub-dialog, make settings as shown in Fig 6.22 Left-click the OK button, then in the main dialog,

click the Set Current button, followed by a left-click on the Close button.

Fig 6.21 The Primary Units

sub-dialog of the Dimension

Style Manager

Fig 6.22 The Tolerances

sub-dialog of the Dimension Style

manager

Fig 6.23 Example – simple

tolerances – outline

Example – simple tolerances (Fig 6.24)

1 Construct the outline in Fig 6.23.

2 Dimension the drawing using either tools from the Dimension toolbar

or by entering abbreviations at the command line Because tolerances

have been set in the Dimension Style Manager dialog, the toleranced

dimensions will automatically be added to the drawing (Fig 6.24)

Example – Geometric tolerances (Fig 6.30)

1 Construct the two rectangles with circles as in Fig 6.25.

2 Add dimensions to the two circles.

3 Click the Tolerance tool icon (Fig 6.26) The Geometrical Tolerance

dialog (Fig 6.27) appears

∅40.00

65.00+0.05–0.05

+0.05 –0.05 +0.05 –0.05

+0.05 –0.05

+0.05 –0.05

245.00 55.00

The dimensions in this drawing show tolerances

Fig 6.24 Example – simple

Fig 6.26 The Tolerance tool icon

in the Dimensions control panel

Fig 6.27 The Geometric

Tolerance dialog and the

Symbol sub-dialog

4 In the dialog click the black box under Sym The Symbol sub-dialog

appears (Fig 6.27) with a click on the top left-hand square.

5 Still in the dialog click the left-hand black square under Tolerance 1 The Material Condition dialog appears (Fig 6.28) Click L The letter

appears in the top right-hand square of the dialog

6 Enter 0.05 in the Tolerance 1 field (Fig 6.29), followed by a click on

the dialog’s OK button The geometrical tolerance appears Move it to

a position near the R10 dimension in the drawing (Fig 6.30).

Fig 6.28 The Geometric

Tolerance dialog and the

Material Condition sub-dialog

Fig 6.29 The completed

Geometric Tolerance dialog

7 Now add a geometrical tolerance to the 15 dimension as shown in

The meanings of the symbols

The Material Condition letters have the following meanings:

M – maximum amount of material

L – least amount of material

S – size within the limits

Fig 6.31 shows the meanings of the geometrical symbols

Text

There are two main methods of adding text to drawings – Multiline Text and Single Line Text.

Example – Single Line Text (Fig 6.24)

1 Open the drawing from the example on tolerances – Fig 6.24.

2 At the command line enter dt (for Single Line Text) followed by a

right-click:

Command: enter dt right-click

TEXT Current text style "ARIAL" Text height: 8 Annotative No:

Specify start point of text or [Justify/Style]: pick

Specify rotation angle of text 0: right-click

Enter text: enter The dimensions in this drawing show tolerances

press the Return key twice

Command:

The result is given in Fig 6.24 on page 116

Notes

1 When using Dynamic Text, the Return key of the keyboard is pressed

after the text has been entered and NOT a right-click.

2 At the prompt:

Specify start point of text or [Justify/Style]: enter s (Style) right-click

Enter style name or [?] ARIAL: enter ? right-click

Enter text style(s) to list *: right-click

Position Concentric

Angular Perpendicular

Parallel Profile (of a surface)

Fig 6.31 The meanings of the

symbols

And an AutoCAD Text Window (Fig 6.32) appears listing all the styles which have been selected in the Text Style (see page 70).

3 In order to select the required text style its name must be entered at the

prompt:

Enter style name or [?] ARIAL: enter Romand right-click

And the text entered will be in the Romand style of height 9 But only

if that style was previously selected in the Text Style dialog.

4 Fig 6.33 shows some text styles from the AutoCAD Text Window.

Fig 6.32 The AutoCAD Text

Window

This is the TIMES text

This is ARIAL text

Fig 6.33 Some text styles

5 There are two types of text fonts available in AutoCAD 2008 – the AutoCAD SHX fonts and the Windows True Type fonts The ITALIC, ROMAND, ROMANS and STANDARD styles shown in Fig 6.33 are AutoCAD text fonts The TIMES and ARIAL styles are Windows True Type styles Most of the True Type fonts can be

entered in Bold, Bold Italic, Italic or Regular styles, but these

varia-tions are not possible with the AutoCAD fonts

6 The Font name popup list of the Text Style dialog shows that a large

number of text styles are available to the AutoCAD 2008 operator It is

Fig 6.34 The Multiline Text tool

icon from the 2D Draw control

panel

advisable to practise using a variety of these fonts to familiarise self with the text opportunities available with AutoCAD 2008

one-Example – Multiline Text (Fig 6.35)

1 Either left-click on the Multiline Text tool icon in the 2D Draw trol panel (Fig 6.34), or click on Multiline Text in the Draw tool- bar, or enter t at the command line:

con-Command:_mtext Current text style: "ARIAL" Text height: 8 Annotative No:

Specify first corner: pick

Specify opposite corner or [Height/Justify/Line spacing/Rotation/

Style/Width/Columns]: pick

As soon as the opposite corner is picked, the Text Formatting dialog

appears and the box changes as in Fig 6.35 Text can now be entered

as required within the box as indicated in this illustration

When all the required text has been entered, left-click the OK button at

the top right-hand corner of the Text Formatting dialog.

Fig 6.35 Example – Multiline

Text entered in the text box

2 Changes can be made to various aspects of the text being entered by

making choices from the various popup lists in the Text Formatting

dialog These popups are shown in Fig 6.36

Symbols used in text

When text has to be added by entering symbols and figures as part of a

dimension, the following keyboard entries must be used:

To obtain Ø75 enter %%c75;

To obtain 55% enter 55%%%;

To obtain 0.05 enter %%p0.05;

To obtain 90 enter 90%%d.